staging: speakup: Fix block comment style

Use trailing */ on a separate line when it is a block comment.
This patch fixes the last of the checkpatch warnings for the file.
Signed-off-by: NJanani Ravichandran <janani.rvchndrn@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/speakup/serialio.c

@@ -8,7 +8,8 @@
 
 #include <linux/serial_core.h>
 /* WARNING:  Do not change this to <linux/serial.h> without testing that
- * SERIAL_PORT_DFNS does get defined to the appropriate value. */
+ * SERIAL_PORT_DFNS does get defined to the appropriate value.
+ */
 #include <asm/serial.h>
 
 #ifndef SERIAL_PORT_DFNS